Needle bar burnishing machine and method



Oct. 19, 1965 M. H. WOLFF 3,212,166

NEEDLE BAR BURNISHING MACHINE AND METHOD Filed Feb. 19, 1962 3 Sheets-Sheet l INVENTOR. I mzz aawa 14 04:; /02 75 BY 75 /00 a 89 M. H. WOLFF Oct. 19, 1965 NEEDLE BAR BURNISHING MACHINE AND METHOD 5 Sheets-Sheet 3 Filed Feb. 19, 1962 INVENTOR. W/ L 0A 14. W04 1 7 United States Patent 3,212,166 NEEDLE BAR BURNISHING MACHINE AND METHOD Mahlon H. Wolff, Hollywood, Caliii, assignor to Neebars, Inc, Los Augeles, Calif. Filed Feb. 19, M62, Ser. No. 174,011 2 Claims. (Cl. 29-90) This invention relates to a machine which is a machine tool for burnishing and polishing, and that is producing a bright mirror finish on metal stock, for example cylindrical steel bars commonly referred to in the art as needle bars. The machine may be used, and the method applied on stock of various sizes and lengths. The primary object of the invention is to make it possible to provide improved finishes on many metal components. These finishes are superior to those possible with ordinary machines of this nature and ordinary grinding methods.

Quite severe service conditions have been imposed by our present high speed space-atomic age necessitating improved finishes on many metal components going into oil country goods, aircraft, nuclear devices and other industrial products.

Up to the present a 32 microinch finish has been considered acceptable for most applications of cold drawn steel bars used as pump shafting for rolls, motors, etc. The herein invention is capable of producing needle bar finishes of 4 R.M.S. on the larger cold drawn steel shafting up to 8 inches diameter. The present invention is capable of consistently producing good mirror finishes of from 3 to 8 R.M.S. without finish grinding or use of special bufiing wheels. The accomplishment of these results and means for doing so are objects of the invention.

The term R.M.S. means root-mean-square average and its connotation herein is known in the art, as respects quality of surface finish. It is a measure of standard of smoothness (or relative roughness). It is expressed by the formula:

average= In the formula, a, b, 0, etc., are the distances in microinches above and below a reference line at n points along the line, the reference line being a mean between peaks and valleys in a surface such that the total area of peaks above the line equals the total area of valleys below it. Peaks and valleys means irregularities.

Some investigators use an arithmetical average as a measure. It is close to the R.M.S. average and some investigators consider it just as effective. It is represented by the formula:

a+b+c+cl+e It will be noted that the R.M.S. average gives greater weight to the larger surface irregularities.

FIGURE 8 illustrates the R.M.S. average and shows in a broken line the magnitude of the improvement offered by this invention.

Further objects include that the mirror finishproduced on shafting has the advantage of substantially increasing the life of the part in field use inasmuch as pitting will produce rapid wear. Furthermore the improved finish wears much less than ordinary polished bars.

Another object and advantage resulting therefrom is that the method actually traps globules of oil used as lubricant into the surface. This has the effect of sealing the surface in oil producing a pore-free surface.

Another object and resulting advantage is to cut production costs considerably due to time savings as compared with centerless grinders. A reduction in production time by one-half is possible saving on delivery time to the customer.

Another object and resulting advantage is to improve the surface finish concentricity as well as closer accuracy and dimensional control.

An example of some of the steel alloys on which the finish has been produced by the herein invention include 4130, 4140, C1045 and stainless alloys such as 303 and 416.

The invention may be practiced on large sized bars and also on bar sizes down to /2 inch or smaller and on all types of materials such as brass, copper and stainless alloys.

Briefly referring to the invention, the cold drawn bars are first roughed in a No. 3 Cincinnati grinder, for example. Then the bars are fed through rolls in the unique burnishing machine of the invention in accordance with the technique or method of the invention. Nearly perfect concentricity is produced. In a preferred form of the machine a pair of idler burnishing rollers is utilized in combination with a driven burnishing roller positioned on the opposite side of the stock which is fed through the rollers. The rollers are symmetrically positioned. The axes of the two idler rollers are at slightly diverging angles as respects the axis of the bar stock being fed through. The axis of the driver burnishing roller is at a slight angle diverging in a vertical plane from the axes of the stock being fed through and also diverging slightly laterally. The burnishing process and the results described above are accomplished by way of several factors. One of these is the angular positioning of the axes of the burnishing rollers as described. Further, the power-driven roller is positionable preferably by pneumatic or hydraulic means and extremely high pressure may be applied to the stock. A lubricant is applied during the processing and it may be a rust preventative oil suitable to the purpose. It contributes to the results in the manner described above. Also contributing to the results is the feed in of the bar which may be by hand or it may be by automatic ma chinery at a rate appropriate to the accomplishment of the results described above.

Further objects and additional advantages of the invention will become apparent from the following detailed description and annexed drawings wherein:

FIGURE 1 is a front view of a preferred form of the machine showing the location of various of its components.

FIGURE 2 is a side view of the machine of FIGURE 1 in perspective, showing the adjusting means for various components.

FIGURE 3 is a rear view of the the position of the burnishing rollers.

FIGURE 4 is a perspective view showing the upper and lower rollers in contact With the work.

FIGURE 5 is a diagrammatic plan view showing the angular displacement of the idler rollers with respect to the axes of the bar stock, and the angular displacement of the axis of the upper driver roller.

FIGURE 6 is a side view of the rollers showing the angular displacement of the axis of the upper roller.

FIGURE 7 is an end view of the rollers showing their relationship to the work.

FIGURE 8 is a diagram illustrating R.M.S. average.

Referring now more in detail to the various figures of the drawings, the machine may be mounted on a suitable type of base as designated at 10. Supported on this base is a structural supporting member 11 and extending laterally from it are structural supporting members 14 and 15 which support a power cylinder 17 which may be either pneumatic or hydraulic and is of a known conventional type which need not be described in detail. The

machine illustrating cylinder 17 is suitably anchored to the support members 14 and 15.

Compressed air for the cylinder 17 is provided by a compressor 19 having a discharge conduit 20 in communioation with the conduit 22 connecting to the cylinder 17. Appropriate automatic controls including control valves, relief valves, etc., may be provided so that the operation of the machine and carrying out the method may be fully automatic if desired.

Upstanding from the supporting bed of the machine are columns 24 and 25, as may be seen in FIGURE 2, and these may be structural steel members or girders.

Numeral 28 designates a frame which may be of any suitable shape such as rectangular formed of structural members 30 and 31, as may be seen in FIGURE 3. Sup-' ported on this frame and attached thereto is another frame designated generally at 34 which may have a shape tapering to the forward part as may be seen in FIGURE 1. The frames may be attached together by way of transverse structural members as designated at 35 and 36. The entire frame assembly is pivotally mounted to move pivotally about a transverse shaft 40. This shaft is not horizontal, but is tilted at a slight angle which 1s the angle Z appearing on FIGURE 6. This angle determines the vertical angle of displacement between the axis of the driver burnishing roller and the axis of the work, that is, the 'bar stock being processed which is designated at 41 in the figures.

The shaft 40 is journalled in journal bearings or pillow blocks 43 and 44 which are mounted on vertical lead screws 47 and 48 which engage with nuts or threaded members mounted on the columns 24 and 25 as designated at 50, 51, 52 and 53. By means of the lead screws the shaft 40 can be adjusted to have any degree of tilt or vertical angular displacement with respect to the axis of the stock 41.

The frame 28 is securely attached to the shaft 40 by way of U-bolts as designated at 58 and 59. As may be seen the entire frame assembly is pivotal about the axis of shaft 40. The adjusted setting of the shaft 40 may be set by means of bolts shown at 62 which secure the pillow blocks 43 and 44 to the upright columns 24 and 25 by way of slots as shown for example at 63 in FIGURE 2.

The power cylinder 17 has an extending stem 18 which is pivotally connected to the forward part of frame 34 of the frame assembly. Carried on the frame assembly is a driving motor 37 which may preferably be an electric motor which drives through a gear train in a gear box 38 having a speed adjusting handle or lever 39. The motor and gear box drive a sprocket wheel on which is a link chain 41' which drives another sprocket wheel 42'. The sprocket wheel 42' is on a shaft 44' journalled in pillow blocks as shown at 47 and 48 in FIGURE 4. These pillow blocks depend downwardly from a supporting platform, bed or table 5% carried on the underside of frame 28. These pillow blocks are slidably mounted in guide slots in the bed or platform 50 and they are adjustable by way of adjusting screws as shown at 52 and 53 in FIG- URES 2 and 4 which have round operating wheels or handles as shown and which cooperate with threaded members or nuts, as shown at 55 and 56 which are secured to the platform or bed 50. By means of these adjustments the lateral angular position or displacement of the shaft 44 laterally as respects the axis of the block 41 may be set. This is angle X in FIGURE 5.

The power driven burnishing roller 60 is mounted on the shaft 44 between the pillow blocks 47 and 48 in a position to engage with the work or stock being processed 41. The pillow blocks themselves may be of conventional construction and need not be described in further detail.

Numeral designates a safety jack having an adjustable stem 71 which is mounted within the machine on the supporting member 11. The purpose of this adjustable jack is to provide an adjustable limit stop to limit the downward movement of the pivoted frame structure so that the stock being worked on cannot be inadvertently damaged since it is possible to exert tremendous forces by way of the power cylind r 1 Supported on the member 11 is a supporting table or platform 75 which supports 2 pairs of pillow blocks 75 and 76 and 78 and 77, shown more in detail in FIG- URE 5. Journalled in the blocks 75 and 76 is shaft 81 and journallcd in the blocks 77 and 78 is a shaft 82. Mounted on shaft 81 is burnishing roller 84 mounted on shaft 82 is burnishing roller 86. All of the rollers may be made of steel, for example. Each of the pillow blocks 75 to 73 is mounted to slide in a groove such as shown at 89 in table or platform 75 as may be seen in FIGURE 4. Each pillow block can be slidably adjusted by means of a lead screw such as is shown, for example, at 90 in FIGURE 4 for the block 75. The lead screw 90 engages a threaded member or nut 91 secured to the slider 92 of the pillow block. Each pillow block is similarly adjustable. In this manner the angular lateral displacement of the shafts 81 and 82, with respect to the axis of the stock 41, can be adjusted and normally the axes of these shafts diverge outwardly slightly from being parallel to the axis of the work or stock 41, the angle between the two shafts being designated at Y in FIGURE 5. The purpose of the angular displacement of the axes of the respective elements will be described presently.

Numeral 95 designates a mounting element or beam which preferably is tubular and which extends outwardly from the base support 11 as shown in the figures. Attached to this supporting beam are a group of clamping brackets, as shown for example at 96 and 97. Extendlng from these clamping brackets are support arms as shown, for example, at 180 in FIGURE 2. Each of these arms is longitudinally slotted and extending through the slot is a screw-threaded support member 102 having preferably a resilient holding or support pad 103 at its end which engages the work piece or stock as may be seen in FIGURE 2. The stem tea may be locked with respect to the support bracket 101 by a lock nut and washer on one side as shown at 104. Any number of support bracket assemblies may be provided as shown in FIG- URE 1 and they can be set in any desired position along the supporting column 95, and the threaded stems can be set in any position along the length of the bracket arms as shown. These support bracket assemblies are positioned along the supporting column 95 in order to support the work piece or bar 41 in such a position that it can be fed through or between the assembly or rollers as illustrated in FIGURES 6 and 7.

Processing and cooling oil is supplied to the area being burnished or processed through a tube or pipe as designated at 106 in FIGURE 2. As explained, this preferably 1s a rust preventative oil having cooling oil consistency and otherwise appropriate to the service being performed.

Numeral 119 designates a vertical stem upstanding from the base and extending through the frame 34. On the end of the stem is an adjustable sleeve or collar 111 engageable with the pivotal frame 34. Handle 112 may operate a limit valve 113 connected to control a valve. The valve 113 operates a main valve which operates the cylinder 17.

From the foregoing those skilled in the art will understand the operation of the machine and the method utilized in the finishing process. The size of the machine and the parts may be varied considerably. The process is accomplished essentially by the several factors outlined in the foregoing. These include the extreme pressure that it is possible to exert by way of the driver roller, which may be as high as 8 tons; the relative angular displacements of the axes of the rollers and the feed stock; the application of the lubricant, and the feeding of the work which is by the angle of the upper wheel or roll 60. The relative relationship of sizes of parts and angles of displacements may in a working embodiment, be approximately those relationships which appear in the figures of the drawings. The spacing between the idler rollers 84 and 86 is adjustable to accommodate to various diameters of work. The diameter of the work stock is otherwise accommodated for by the positioning of the pivotal frame 34. The angle of displacement of the various axes is adjusted in the manner described above. The following approximate exemplary dimensions are given as representative of one working embodiment of the invention. The diameters of the idler rollers 84 and 86 are approximately 6 inches. The driver roller 60 is 6 inches in diameter with an axial length of 3 inches whereas the axial length of the idler rollers is 6 inches. The lateral angle Y between the axes of the idler rollers might be from 4 to 5 degrees to 18 degrees so that the axis of each of these rollers is displaced laterally half this amount from the axis of the stock 41. The axis of the driver roller 60 is inclined in a latenal plane to the axis of the stock 41, as described, and this angle X as shown in FIGURE 5 may correspond to the lateral angle of displacement of the axes of the idler rollers'from the axis of the stock. The angles may be varied depending upon the type of material worked on and the size and the exact type of finish it is desired to produce. Angle Z, FIGURE 6, may correspond to the other displacement angles or may be less. It will be observed that the entire surface of the rollers does not engage the stock being worked on, but rather a part of the surface depending on the angles of displacement. The displacement angles are important to the finishing and contribute to the driving and feeding of the stock. The work is put in manually and it is rotated by the driver roller which exerts a pressure on it. In an example, compatible with the figures given above, the stock might be a bar 22 feet long having a force of 640 pounds applied to it. The engagement of the rollers with the stock, that is, the needle blar burnishes and polishes the bar producing finishes of the quality described in the foregoing. Finish grinding or special bufling wheels are not required.

From the foregoing those skilled in the art will observe that the invention as described herein achieves all of the objects and realizes all of the advantages set forth in the foregoing. It provides for producing mirror finishes of superior quality and as necessary to meet many service conditions brought about by the present high speed spaceatomic age.

The foregoing is illustrative of a preferred form of the invention and is to be interpreted in an illustrative rather than a limiting sense. The machine and method of the invention may be practiced in other modified and equivalent forms within the spirit and scope of the invention which is to be in accordance with the scope of the claims appended hereto.

What is claimed is:

1. A burnishing machine comprising means to support bar stock for axial feeding of the bar stock with respect to roller means; roller means including a. driven burnishing roller having a peripheral surface part which is en gageable with the surface of the bar stock for burnishing; said peripheral surf-ace being substantially parallel to the axis of the burnishing roller; the axis of said burnishing roller having an angular displacement from the axis of the bar stock; the axis of the burnishing roller having a second angular displacement from the axis of the bar stock, said second angular displacement lying in a plane which intersects angularly with respect to the axis of the bar stock 90 from the plane containing the first mentioned angular displacement and said means to support said bar stock including an additional pair of idler burnishing rollers positioned to engage the bar stock in opposition to said driven burnishing roller; the axes of said additional pair of idler burnishing rollers lying in a plane parallel to the axis of the bar stock.

2. A burnishing machine as claimed in claim 1 wherein the additional pair of idler burnishing rollers is positioned so that their axes lie in a plane including the axis of the bar stock and the axes of said pair of rollers diverging opposite from the axis of the bar stock in a plane parallel to the axis of the bar stock.

References Cited by the Examiner UNITED STATES PATENTS 149,309 4/74 Hayden --l3 374,703 12/87 Ritchie 8013 387,971 8/88 Farmer 29-81.6 X

648,080 4/00 Quimby 8013 896,851 8/08 McCarren 2981.6 1,082,544 12/ 13 Mathews 29-81.6 1,521,735 1/25 Vlahos 29 X 1,887,434 11/32 Sammis 29-81.6 X

FOREIGN PATENTS 808,197 7/51 Germany.

705,793 3/54 Great Britain.

162,038 2/58 Sweden.

RICHARD H. EANES, JR., Primary Examiner. WILLIAM W. DYER, JR., Examiner. 

1. A BURNISHING MACHINE COMPRISING MEANS TO SUPPORT BAR STOCK FOR AXIAL FEEDING OF THE BAR STOCK WITH RESPECT TO ROLLER MEANS; ROLLER MEANS INCLUDING A DRFIVEN BURNISHING ROLLER HAVING A PERIPHERAL SURFACE PART WHICH IS ENGAGEABLE WITH THE SURFACE OF THE BAR STOCK FOR BURNISHING; SAID PERIPHERAL SURFACE BEING SUBSTANTIALLY PARALLEL TO THE AXIS OF THE BURNISHING ROLLER; THE AXIS OF SAID BURNISHING ROLLER HAVING AN ANGULAR DISPLACEMENT FROM THE AXIS OF THE BAR STOCK; THE AXIS OF THE BURNISHING ROLLER HAVING A SECOND ANGULAR DISPLACEMENT FROM THE AXIS OF THE BAR STOCK, SAID SECOND ANGULAR DISPLACEMENT LYING IN A PLANE WHICH INTERSECTS ANGULARLY WITH RESPECT TO THE AXIS OF THE BAR STOCK 90* FROM THE PLANE CONTAINING THE FIRST MENTIONED ANGULAR DISPLACEMENT AND SAID MEANS TO SUPPORT SAID BAR STOCK INCLUDING AN ADDITIONAL PAIR OF IDLER BURNISHING ROLLERS POSITIONED TO ENGAGE THE BAR STOCK IN OPPOSITION TO SAID DRIVEN BURNISHING ROLLER; THE AXES OF SAID ADDITIONAL PAIR OF IDLER BURNISHING ROLLERS LYING IN A PLANE PARALLEL TO THE AXIS OF THE BAR STOCK. 